Abstract: A semiconductor device includes a first switching device including a first electrode coupled with a first node, a second electrode coupled with a second node, and a first control electrode controlling connection between the first and second electrodes; a second switching device including a third electrode coupled with the second node, a fourth electrode coupled with the second node, and a second control electrode controlling the connection between the third electrode and the fourth electrode; and a first control circuit controlling a substrate voltage of the second switching device.

Abstract: A semiconductor device is described which includes a first comparator judging the level of an input signal based on a first judgment value, a second comparator judging the level of the input signal based on a second judgment value, and a calibrator outputting a control signal for starting the calibration of the second judgment value in the case that the calibration of the first judgment value is ended.

Abstract: A digital analog converter has an input terminal receiving a digital input signal, a lower-side capacitor group coupled to a lower-side common terminal in parallel, an upper-side capacitor group coupled, in parallel, to an upper-side common terminal at which an analog output signal is generated, a coupling capacitor provided between the lower-side common terminal and the upper-side common terminal, a switch group coupled to the upper-side capacitor group and the lower-side capacitor group and controlled as a conduction state and a non-conduction state in accordance with the digital input signal, and an adjusting capacitor coupled to the lower-side common terminal and having a variable capacitance value.

Abstract: An analog signal processing device including a voltage selector selecting a given comparison reference voltage from plural comparison reference voltages, an arithmetic unit arithmetically processing the given comparison reference voltage and an analog input signal, a comparator which has at least one or more judgment points for the plural comparison reference voltages and to which an output of the arithmetic unit is inputted, and a coupling controller controlling connections between the arithmetic unit and the comparator, wherein the arithmetic unit comprises correctable first signal processors, and the number of the first signal processors is more than is necessary for the plural comparison reference voltages by M or larger, and when a set of N of first signal processors are in a correction operation, the coupling controller connects first signal processors which are not in the correction operation in the arithmetic unit to the comparator.

Abstract: A high speed A/D converter includes a series of encoder sections for converting a thermometer code to a gray code and an error signal production section for detecting a babble error in the gray code and generating an error signal indicating such a babble error. An error correction section corrects babble errors in the gray code in response to the error signal. The corrected gray code is then converted to a binary code with a gray code to binary code converter. When the high speed A/D converter is incorporated in a semiconductor device, the A/D converter may be tested using a sampling clock having a phase which varies successively with respect to the input analog signal to sample the analog signal, and then evaluating the corresponding generated digital signal.

Abstract: A high speed A/D converter includes a series of encoder sections for converting a thermometer code to a gray code and an error signal production section for detecting a babble error in the gray code and generating an error signal indicating such a babble error. An error correction section corrects babble errors in the gray code in response to the error signal. The corrected gray code is then converted to a binary code with a gray code to binary code converter. When the high speed A/D converter is incorporated in a semiconductor device, the A/D converter may be tested using a sampling clock having a phase which varies successively with respect to the input analog signal to sample the analog signal, and then evaluating the corresponding generated digital signal.

Abstract: An A/D converter includes a bit cell for converting an analog input signal to a single-bit digital signal. The bit cell includes an operational circuit for performing at least one of a first operation (Vin−VRH)+(Vin−VRL) and a second operation (VRH−Vin)+(VRL−Vin), where VRH is a high potential reference voltage, VRL is a low potential reference voltage and Vin is the analog input signal.

Abstract: An A/D converter comprises: a differential amplifier row for amplifying differential voltages between an analog input voltage and reference voltages; a first sample/hold circuit row for sampling/holding the individual differential voltages amplified; a second sample/hold circuit having a pair of second and third sample/hold circuits connected in parallel to each output of the first sample/hold circuit row, thereby performing alternate sampling; a plurality of comparators for determining whether the individual differential voltages held by the first sample/hold circuit row are positive or negative; and an encoder for outputting digital code corresponding to the outputs of the comparators.

Abstract: An A/D converter comprises: a differential amplifier row for amplifying differential voltages between an analog input voltage and reference voltages; a first sample/hold circuit row for sampling/holding the individual differential voltages amplified; a second sample/hold circuit having a pair of second and third sample/hold circuits connected in parallel to each output of the first sample/hold circuit row, thereby performing alternate sampling; a plurality of comparators for determining whether the individual differential voltages held by the first sample/hold circuit row are positive or negative; and an encoder for outputting digital code corresponding to the outputs of the comparators.

Abstract: In a D/A conversion apparatus capable of achieving high accuracy formation of output voltage of an analog signal, when data D7 through D0 of 8 bits are inputted to a decoder 4, by a control signal from the decoder 4, a pair of switches connected to both ends of predetermined resistor R0 are selected from respective switches S0A through S255A, S0B through S255B of respective switch groups 3A, 3B of a voltage selecting circuit 3 and simultaneously operated to make ON and the other respective switches are operated to make OFF. Further, voltage across both sides of resistor R0 of a voltage generating circuit 2 connected with the pair of switches operated to make ON is inputted to a differential amplifier 5 and average voltage of the voltage across the both ends of the resistor R0 connected with the switches operated to make ON is outputted from an output terminal 6 as an analog signal.

Abstract: In a D/A conversion apparatus capable of achieving high accuracy formation of output voltage of an analog signal, when data D7 through D0 of 8 bits are inputted to a decoder 4, by a control signal from the decoder 4, a pair of switches connected to both ends of predetermined resistor R0 are selected from respective switches S0A through S255A, S0B through S255B of respective switch groups 3A, 3B of a voltage selecting circuit 3 and simultaneously operated to make ON and the other respective switches are operated to make OFF. Further, voltage across both sides of resistor R0 of a voltage generating circuit 2 connected with the pair of switches operated to make ON is inputted to a differential amplifier 5 and average voltage of the voltage across the both ends of the resistor R0 connected with the switches operated to make ON is outputted from an output terminal 6 as an analog signal.

Abstract: A high speed A/D converter includes a series of encoder sections for converting a thermometer code to a gray code and an error signal production section for detecting a babble error in the gray code and generating an error signal indicating such a babble error. An error correction section corrects babble errors in the gray code in response to the error signal. The corrected gray code is then converted to a binary code with a gray code to binary code converter. When the high speed A/D converter is incorporated in a semiconductor device, the A/D converter may be tested using a sampling clock having a phase which varies successively with respect to the input analog signal to sample the analog signal, and then evaluating the corresponding generated digital signal.

Abstract: A high speed A/D converter includes a series of encoder sections for converting a thermometer code to a gray code and an error signal production section for detecting a babble error in the gray code and generating an error signal indicating such a babble error. An error correction section corrects babble errors in the gray code in response to the error signal. The corrected gray code is then converted to a binary code with a gray code to binary code converter. When the high speed A/D converter is incorporated in a semiconductor device, the A/D converter may be tested using a sampling clock having a phase which varies successively with respect to the input analog signal to sample the analog signal, and then evaluating the corresponding generated digital signal.

Abstract: A series to parallel A/D type converter converts an analog input signal to a digital output signal. The A/D converter has an upper rank comparator which performs A/D conversion of upper order bits and a lower rank comparator which performs A/D conversion of lower order bits. An input control circuit receives the analog input signal and generates a first input signal which is provided to the upper rank comparator and generates a second input signal which is provided to the lower rank comparator. Both the upper and lower rank comparators receive the respective first and second input signal from the input control circuit and compare the respective input signals with predetermined reference voltages to generate a digital output signal.

Abstract: A high speed A/D converter includes a series of encoder sections for converting a thermometer code to a gray code and an error signal production section for detecting a babble error in the gray code and generating an error signal indicating such a babble error. An error correction section corrects babble errors in the gray code in response to the error signal. The corrected gray code is then converted to a binary code with a gray code to binary code converter. When the high speed A/D converter is incorporated in a semiconductor device, the A/D converter may be tested using a sampling clock having a phase which varies successively with respect to the input analog signal to sample the analog signal, and then evaluating the corresponding generated digital signal.

Abstract: An encoder for an A/D converter includes a plurality of ROM cells connected between bit lines and word lines. Each of the ROM cells is responsive to a word line select signal supplied to a word line associated with each of the ROM cells for supplying a digital output signal according to the word line select signal to a bit line associated with each of the ROM cells. A logic processor is coupled to one of the bit lines and to two of the word lines used to select a ROM cell connected to the bit line. The logic processor produces an output signal indicative of a selection of the ROM cell connected to the bit line, based on word line select signals supplied on the two word lines.

Abstract: An encoder for an A/D converter includes a plurality of ROM cells connected between bit lines and word lines. Each of the ROM cells is responsive to a word line select signal supplied to a word line associated with each of the ROM cells for supplying a digital output signal according to the word line select signal to a bit line associated with each of the ROM cells. A logic processor is coupled to one of the bit lines and to two of the word lines used to select a ROM cell connected to the bit line. The logic processor produces an output signal indicative of a selection of the ROM cell connected to the bit line, based on word line select signals supplied on the two word lines.

Abstract: An interleaved auto-zero analog-to-digital converter includes chopper comparators for comparing an analog input signal to predetermined voltage values. An additional chopper comparator is included for performing the comparison function of a chopper comparator undergoing an auto zero operation.

Abstract: An encoder for an A/D converter includes a plurality of ROM cells connected between bit lines and word lines. Each of the ROM cells is responsive to a word line select signal supplied to a word line associated with each of the ROM cells for supplying a digital output signal according to the word line select signal to a bit line associated with each of the ROM cells. A logic processor is coupled to one of the bit lines and to two of the word lines used to select a ROM cell connected to the bit line. The logic processor produces an output signal indicative of a selection of the ROM cell connected to the bit line, based on word line select signals supplied on the two word lines.